The name VAREX is known around the world as a synonym for powerful and reliable extrusion of high quality blown film. With the development and upgrading of the VAREX, German based engineering company Windmöller & Hölscher (W&H), with headquarters in Lengerich/Westphalia, has succeeded in constantly setting new benchmarks in regard to productivity, film quality and flexibility of applications. Since entering the extrusion technology market in 1967, W&H has launched more than 2000 systems with over 5000 extruders.
With VAREX II, W&H now presents the innovative successor to the renowned VAREX blown film system and in doing so lifts the secret of one of the most significant development projects in the company's history. At the W&H stand, visitors will have the opportunity to see a 2200 mm 5-layer extrusion line featuring the MAXICONE P die, which is specially designed for polyolefin films. The demo product is 40-micron collation shrink film, produced at an exceptionally high speed.
"Designed by Experience"
VAREX II – the new generation blown film extrusion concept
VAREX II combines the knowledge and experience gathered over many decades with continuous development and upgrading of each and every component of the line. The underlying goal was to consistently increase the productivity and flexibility as well as improve the film quality, while at the same time giving due consideration to sustainability and ergonomic design.
The VAREX II is modularly designed and can therefore be tailored to any user specific requirements and production environments as well as to the product portfolio to be handled. The modular concept also allows for later retrofitting with optional modules and new technologies to accommodate future requirements as and when the need arises. In this way the latest state of the art is guaranteed for the extrusion line at all times. The consistent integration of all components into a central line control system ensures ease of operation and monitoring from an ergonomically optimized central operating unit.
All system components are laid out to guarantee reproducible production of superb film quality at maximum output rates. The extruders are, therefore, of utmost importance. Owing to the powerful flow-optimized barrier screws, W&H extruders provide maximum flexibility with the processing of the most diverse resins. The broad selection of MAXICONE dies available ensures that there will be the correct die for any product specification. The patented melt distribution system allows for an extremely compact design and keeps pressure losses low. In this way high melt throughputs and very tight film gauge tolerances are achieved. OPTIFIL P, W&H's proven gauge profile control system enables targeted control of the melt temperature on the bubble circumference, reducing film gauge tolerances to the very minimum. The result is reduced resin usage and optimum quality of the film produced. One of the many highlights of the VAREX II is the new bubble collapsing unit in the film haul-off. Thanks to the automatic adjustment of the lateral guide elements, film flatness is improved and film curvature minimized. Featuring a comprehensive range of optional specifications, the new FILMATIC S II winder can be tailored to any application and will produce perfect roll quality, even when handling highly sophisticated film products.
ARCTIS – innovative air ring system for maximum output
Effective film cooling is a requirement for maximum productivity. The new ARCTIS air ring, an upgrade of the OPTICOOL high-performance air ring presented in 2009, substantially contributes to a further increase in output. The innovative air flow concept leads to maximum cooling efficiency and optimum performance. The unique integrated design concept of the air ring provides easy access to the die components.
A word on sustainability:
Sustainable handling across the entire process chain – from resin manufacturing to the end user – has been gaining increasing importance also in regard to film production. That's why, throughout the development of VAREX II, the focus has been on sustainability. Featuring a great number of innovative engineering solutions, the VAREX II sets new standards in regard to raw material and energy efficiency. The result is perfect film width tolerances, eliminating the need for edge trimming in the majority of applications. Thanks to EASY-CHANGE, the autopilot for size change-overs, EASY-WIND, the winder control concept for optimum film roll quality, PROFILE BOOSTER to accelerate line start-up, and PURGE ASSIST for automatic purging of the extruders and dies, waste is minimized and efficiency maximized.
Other automation modules available for the VAREX II are aimed at a greater transparency of the production process. The ENERGY MONITORING module ascertains and displays the energy usage of the individual modules, in this way identifying possible savings potential in the course of the production process. The ISP module collects and saves all production parameters and enables detailed monitoring of the production process, providing a basis for efficient quality assurance. The ISP based module PPS (Production Planning and Control) is a new feature permitting, for the first time, decentralized job preparation and control. Order specifications and product formulations can be directly transmitted from the on-site ERP system to the extrusion line, without the operator having to enter any order data locally on the machine.
The VAREX II is available with working widths up to 3600 mm and for up to 11-layer films. It is designed for outputs up to 1500 kg/h. Extruder sizes include 50, 60, 70, 90, 105, 120 and 135.30 D. Die diameters range from 120 to 900 mm.
Windmöller & Hölscher (W&H) is an internationally leading manufacturer of machinery and equipment for flexible packaging applications. The product line encompasses blown and cast film lines, flexographic and gravure printing presses, finishing and converting machines for paper, film, foil, and woven plastic materials, as well as FFS (form-fill-seal) packaging systems.